Injection molding system and method for manufacturing molded object

ABSTRACT

An injection molding system includes: an injection molding machine; an inspection device including a first placement unit, a second placement unit, an inspection unit, and a moving unit configured to change a relative position between the first placement unit and the inspection unit and a relative position between the second placement unit and the inspection unit; a third placement unit; a robot configured to convey the molded object; and a control device. The control device controls the injection molding machine, the robot, and the inspection device so as to mold a first molded object during a first molding period, inspect the first molded object placed on the first placement unit during a first inspection period, convey the first molded object after inspection from the first placement unit to the third placement unit during a first conveyance period, mold a second molded object during a second molding period, inspect the second molded object placed on the second placement unit during a second inspection period, convey the second molded object after inspection from the second placement unit to the third placement unit during a second conveyance period, and overlap the first inspection period and the second molding period and overlap the second inspection period and the first conveyance period.

The present application is based on, and claims priority from JPApplication Serial Number 2019-169954, filed Sep. 19, 2019, thedisclosure of which is hereby incorporated by reference herein in itsentirety.

BACKGROUND 1. Technical Field

The present disclosure relates to an injection molding system and amethod for manufacturing a molded object.

2. Related Art

JP-A-2005-014224 discloses a device that takes out by a robot, a moldedobject molded by an injection molding machine from a mold, conveys themolded object to an inspection device, and conveys the molded objectafter inspection from the inspection device to a stage.

As in the device described above, in a device that inspects the moldedobject molded by the injection molding machine and conveys the moldedobject after the inspection, there is a possibility that a step ofinspecting the molded object becomes a bottleneck, resulting in a longercycle time. Therefore, there is room for further improvement in order toimprove the cycle time.

SUMMARY

According to one aspect of the present disclosure, an injection moldingsystem is provided. The injection molding system includes: an injectionmolding machine configured to inject a molten material into a mold tomold a molded object; an inspection device including a first placementunit and a second placement unit on which the molded object is placed,an inspection unit configured to inspect the molded object, and a movingunit configured to change a relative position between the firstplacement unit and the inspection unit and a relative position betweenthe second placement unit and the inspection unit; a third placementunit on which the molded object after inspection by the inspectiondevice is placed; a robot configured to execute an operation ofconveying the molded object from the mold to the first placement unit orthe second placement unit, and an operation of conveying the moldedobject from the first placement unit or the second placement unit to thethird placement unit; and a control device configured to control theinjection molding machine, the robot, and the inspection device. Thecontrol device controls the injection molding machine, the robot, andthe inspection device so as to mold, by the injection molding machine, afirst molded object as the molded object during a first molding period,inspect, by the inspection unit, the first molded object placed on thefirst placement unit during a first inspection period, convey, by therobot, the first molded object after inspection from the first placementunit to the third placement unit during a first conveyance period, mold,by the injection molding machine, a second molded object as the moldedobject during a second molding period after the first molding period,inspect, by the inspection unit, the second molded object placed on thesecond placement unit during a second inspection period, convey, by therobot, the second molded object after inspection from the secondplacement unit to the third placement unit during a second conveyanceperiod, and overlap the first inspection period and the second moldingperiod and overlap the second inspection period and the first conveyanceperiod.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a first perspective view showing a schematic configuration ofan injection molding system according to a first embodiment.

FIG. 2 is a second perspective view showing the schematic configurationof the injection molding system according to the first embodiment.

FIG. 3 is a front view showing a schematic configuration of theinjection molding system according to the first embodiment.

FIG. 4 is a top view showing the schematic configuration of theinjection molding system according to the first embodiment.

FIG. 5 is a view showing a configuration of an injection moldingmachine.

FIG. 6 is a perspective view showing a configuration of a flat screw ona groove forming surface side.

FIG. 7 is a view showing a configuration of a barrel on a screw facingsurface side.

FIG. 8 is a perspective view showing a configuration of an inspectiondevice.

FIG. 9 is a first top view showing a configuration of a tray movingunit.

FIG. 10 is a second top view showing the configuration of the traymoving unit.

FIG. 11 is a diagram showing a process of manufacturing a molded objectby the injection molding system.

FIG. 12 is a time chart showing the process of manufacturing the moldedobject by the injection molding system.

FIG. 13 is a flowchart showing contents of a molding processing.

FIG. 14 is a first diagram showing a state in which the molded object isprotruded by an ejector pin.

FIG. 15 is a second diagram showing a state in which the molded objectis protruded by the ejector pin.

FIG. 16 is a third diagram showing a state in which the molded object isprotruded by the ejector pin.

FIG. 17 is a reference diagram showing a state in which the moldedobject is protruded by the ejector pin.

FIG. 18 is a first diagram showing an operation of the tray moving unit.

FIG. 19 is a second diagram showing an operation of the tray movingunit.

FIG. 20 is a third diagram showing an operation of the tray moving unit.

FIG. 21 is a fourth diagram showing an operation of the tray movingunit.

FIG. 22 is a fifth diagram showing an operation of the tray moving unit.

FIG. 23 is a time chart showing a process of manufacturing the moldedobject according to a comparative example.

DESCRIPTION OF EXEMPLARY EMBODIMENTS A. First Embodiment

FIG. 1 is a first perspective view showing a schematic configuration ofan injection molding system 10 according to a first embodiment. FIG. 2is a second perspective view showing the schematic configuration of theinjection molding system 10 according to the first embodiment. FIG. 3 isa front view showing the schematic configuration of the injectionmolding system 10 according to the present embodiment. FIG. 4 is a topview showing the schematic configuration of the injection molding system10 according to the present embodiment. In FIGS. 1 to 4 , arrows alongX, Y, and Z directions that are orthogonal to each other are shown. TheX direction and the Y direction are directions along a horizontaldirection, and the Z direction is a direction along a verticaldirection. In other figures, arrows along the X, Y, and Z directions areappropriately shown. The X, Y, and Z directions in FIGS. 1 to 4 and theX, Y, and Z directions in other figures represent the same direction.

The injection molding system 10 according to the present embodimentincludes an injection molding machine 100, a robot 200, an inspectiondevice 300, a tray moving unit 400, and a control device 500, which aredisposed in one housing 50. The housing 50 includes a first base 51 anda second base 52. The injection molding machine 100, the robot 200, andthe inspection device 300 are disposed on an upper surface of the firstbase 51. The robot 200 is disposed on a +Y direction side with respectto the injection molding machine 100. The inspection device 300 isdisposed on a −X direction side with respect to the injection moldingmachine 100. The first base 51 is provided with an opening portion. Thesecond base 52 is provided below the first base 51. The tray moving unit400 is disposed on an upper surface of the second base 52. The injectionmolding machine 100 is disposed above the tray moving unit 400 in avertical direction. At least a part of the injection molding machine 100vertically overlaps the tray moving unit 400. The inspection device 300is disposed above the tray moving unit 400 in the vertical direction. Atleast a part of the inspection device 300 vertically overlaps the traymoving unit 400. A space between the first base 51 and the second base52 communicates with a space above the first base 51 via an openingportion provided in the first base 51. The control device 500 isdisposed below the second base 52. A caster 58 for moving the housing 50and a stopper 59 for fixing the housing 50 are provided on a lowersurface of the housing 50. An operation panel 55 is provided in a frontportion of the housing 50. In the present embodiment, the operationpanel 55 is implemented by a touch panel. In FIGS. 1 to 3 , theinspection device 300 is not illustrated.

The tray moving unit 400 moves a tray TR for conveying a molded object.The tray moving unit 400 is provided with a tray discharging mechanism405. As shown in FIG. 2 , the tray discharging mechanism 405 protrudestoward the outside of the housing 50 to discharge the tray TR to theoutside of the housing 50. A detailed configuration of the traydischarging mechanism 405 will be described later. The tray TR may bereferred to as a third placement position.

As shown in FIG. 3 , a material supply unit 105 is disposed below thesecond base 52 of the housing 50. A material in a state of pellets,powder, or the like is accommodated in the material supply unit 105. Inthe present embodiment, a pellet-shaped ABS resin is used as thematerial. The material supply unit 105 is coupled to a material storageunit 110 of the injection molding machine 100 via a material supply pipe106. A compressor 107 is coupled to the material supply unit 105. Thecompressor 107 supplies compressed air to the material supply unit 105,and pumps a material from the material supply unit 105 to the materialstorage unit 110 via the material supply pipe 106. The compressor 107 isdriven under control of the control device 500.

At a taking-out position P11 shown in FIG. 4 , the robot 200 takes outthe molded object from a mold unit 160 of the injection molding machine100 to convey the molded object. In the present embodiment, the robot200 includes an arm unit 210, a suction unit 250, and a robot controlunit 290. The arm unit 210 moves a position of the suction unit 250. Thearm unit 210 rotates a direction of the suction unit 250. The suctionunit 250 sucks the molded object by vacuum suction. The robot controlunit 290 is implemented by a computer including one or more processors,a main storage device, and an input and output interface for inputtingand outputting signals to and from the outside. In the presentembodiment, the robot control unit 290 executes a program or a commandread on the main storage device by the processor to control the arm unit210 and the suction unit 250. The robot control unit 290 operates in arobot language. As the robot language, for example, an SPEL language isused. The robot 200 may include a sandwiching unit configured tosandwich the molded object instead of the suction unit 250 configured tosuck the molded object.

The control device 500 is implemented by a computer including one ormore processors, a main storage device, and an input and outputinterface for inputting and outputting signals to and from the outside.In the present embodiment, the control device 500 is implemented by aprogrammable logic controller (PLC) operating in a ladder language. Inthe present embodiment, the control device 500 executes a program or acommand read on the main storage device by the processor to supply thematerial from the material supply unit 105 to the injection moldingmachine 100, mold the molded object by the injection molding machine100, convey the molded object to the inspection device 300 by the robot200, inspect the molded object by the inspection device 300, convey theinspected molded object to the tray TR by the robot 200, and dischargeby the tray moving unit 400 the tray TR on which the molded object isplaced to the outside of the housing 50. The control device 500 controlsthe injection molding machine 100, the robot 200, the inspection device300, and the tray moving unit 400 so that the start timing of eachoperation is a predetermined timing.

The compressor 107 coupled to the material supply unit 105, theinjection molding machine 100, the inspection device 300, and the traymoving unit 400 operate in accordance with commands generated using theladder language. The arm unit 210 and the suction unit 250 of the robot200 operate in accordance with commands generated using the robotlanguage. The control device 500 transmits the commands generated usingthe ladder language to the compressor 107, the injection molding machine100, the inspection device 300, and the tray moving unit 400 to controloperations of the compressor 107, the injection molding machine 100, theinspection device 300, and the tray moving unit 400. The control device500 transmits a command generated using the ladder language andinterpretable in the robot language to the robot control unit 290 tocontrol operations of the arm unit 210 and the suction unit 250 by therobot control unit 290. The ladder language may be referred to as afirst language, and the robot language may be referred to as a secondlanguage.

FIG. 5 is a diagram showing a schematic configuration of the injectionmolding machine 100. The injection molding machine 100 according to thepresent embodiment includes the above-described material storage unit110, a plasticization unit 120, an injection control mechanism 150, anozzle 155, the mold unit 160, and a mold clamping device 170. Theinjection molding machine 100 injects a molten material from the nozzle155 to the mold unit 160 to mold a molded object.

The material storage unit 110 stores the material supplied from thematerial supply unit 105 via the material supply pipe 106. The materialstorage unit 110 in the present embodiment is implemented by a hopper.The material storage unit 110 is in communication with theplasticization unit 120 and supplies the material to the plasticizationunit 120.

The plasticization unit 120 includes a screw case 121, a drive motor122, a flat screw 130, a barrel 140, and a heating unit 148. Theplasticization unit 120 plasticizes at least a part of the material inpellet form supplied from the material storage unit 110, and generates amolten material in paste form having fluidity, and then guides themolten material to the injection control mechanism 150. The term“plasticize” refers to that the material having thermoplasticity isheated and melted. The term “melt” means not only that the materialhaving thermoplasticity is heated to a temperature equal to or higherthan a melting point to become a liquid, but also that the materialhaving thermoplasticity is softened by being heated to a temperatureequal to or higher than a glass transition point, and exhibits fluidity.

The flat screw 130 has a substantially columnar shape whose height in adirection along a central axis RX thereof is smaller than a diameter.The flat screw 130 is accommodated in a space surrounded by the screwcase 121 and the barrel 140. The flat screw 130 has a groove formingsurface 132 provided with a groove portion 135, which is on a surface ofthe flat screw 130 facing the barrel 140. The drive motor 122 is coupledto a surface of the flat screw 130 opposite to the groove formingsurface 132. The flat screw 130 rotates about the central axis RX bytorque generated by the drive motor 122. The drive motor 122 is drivenunder the control of the control device 500.

FIG. 6 is a perspective view showing a configuration of the flat screw130 on a groove forming surface 132 side. In FIG. 6 , a position of thecentral axis RX of the flat screw 130 is shown by a dashed line. Asdescribed with reference to FIG. 5 , the groove portion 135 is providedin the groove forming surface 132. A central portion 137 of the grooveforming surface 132 of the flat screw 130 is implemented as a recess towhich one end of the groove portion 135 is coupled. The central portion137 faces a communication hole 146 of the barrel 140 shown in FIG. 5 .The central portion 137 intersects the central axis RX.

The groove portion 135 of the flat screw 130 constitutes a so-calledscroll groove. The groove portion 135 extends from the central portion137 toward an outer periphery of the flat screw 130 in a form of swirlso as to draw an arc. The groove portion 135 may be configured to extendspirally. The groove forming surface 132 is provided with ridge portions136 that form side wall portions of respective groove portions 135 andextend along the respective groove portions 135. The groove portion 135is continuous to a material introduction port 134 formed in a sidesurface 133 of the flat screw 130. The material introduction port 134 isa portion for receiving the material in the groove portion 135.

FIG. 6 shows an example of the flat screw 130 including three grooveportions 135 and three ridge portions 136. The number of the grooveportions 135 or the ridge portions 136 provided in the flat screw 130 isnot limited to three. The flat screw 130 may be provided with only onegroove portion 135, or may be provided with two or more groove portions135. Any number of the ridge portions 136 may be provided in accordancewith the number of the groove portions 135.

FIG. 6 illustrates an example of the flat screw 130 in which thematerial introduction port 134 is formed at three places. The number ofthe material introduction ports 134 provided in the flat screw 130 isnot limited to three. In the flat screw 130, the material introductionport 134 may be provided at only one place, or may be provided at two ormore places.

FIG. 7 is a view showing a configuration of the barrel 140 on a screwfacing surface 142 side. Referring to FIGS. 5 and 7 , the barrel 140includes a screw facing surface 142 that faces the groove formingsurface 132 of the flat screw 130. The communication hole 146communicating with the nozzle 155 is provided at a center of the screwfacing surface 142. A plurality of guide grooves 144 are provided aroundthe communication hole 146 in the screw facing surface 142. One end ofthe guide groove 144 is coupled to the communication hole 146, andextends in a form of swirl from the communication hole 146 toward anouter periphery of the screw facing surface 142. The guide groove 144has a function of guiding a shaping material to the communication hole146. The screw facing surface 142 may be simply referred to as a facingsurface.

The heating unit 148 is embedded in the barrel 140. In the presentembodiment, the heating unit 148 includes four heaters. A temperature ofthe heating unit 148 is controlled by the control device 500. Byrotation of the flat screw 130 and the heating by the heating unit 148,the material supplied to the groove portion 135 is melted to generatethe molten material, and then the molten material is supplied to theinjection control mechanism 150 through the communication hole 146.

Referring to FIG. 5 , the injection control mechanism 150 includes aninjection cylinder 151, a plunger 152, and a plunger drive unit 153. Theinjection control mechanism 150 has a function of injecting theplasticized material in the injection cylinder 151 into a cavity Cv tobe described later. The injection control mechanism 150 controls aninjection amount of the material from the nozzle 155 under the controlof the control device 500. The injection cylinder 151 is a substantiallycylindrical member coupled to the communication hole 146 of the barrel140, and includes the plunger 152 therein. The plunger 152 slides insidethe injection cylinder 151 and pumps the material in the injectioncylinder 151 to a nozzle 155 side coupled to the plasticization unit120. The plunger 152 is driven by the plunger drive unit 153 implementedby a motor, a gear, or the like.

The mold unit 160 includes a movable mold 161 and a fixed mold 162. Themovable mold 161 and the fixed mold 162 are provided to face each other,and the cavity Cv that is a space corresponding to a shape of the moldedobject is formed between the movable mold 161 and the fixed mold 162.The plasticized material is pumped to the cavity Cv by the injectioncontrol mechanism 150 and injected via the nozzle 155. In the presentembodiment, the movable mold 161 and the fixed mold 162 are formed of ametal material. The movable mold 161 and the fixed mold 162 may beformed of a ceramic material or a resin material. The mold unit 160 maybe referred to as a mold portion, and the movable mold 161 may bereferred to as a movable mold, and the fixed mold 162 may be referred toas a fixed mold.

The mold clamping device 170 includes a mold drive unit 171 and a ballscrew unit 172, and has a function of opening and closing the movablemold 161 and the fixed mold 162. The mold drive unit 171 is implementedby a motor, a gear, or the like. The mold drive unit 171 is coupled tothe movable mold 161 via the ball screw unit 172. The ball screw unit172 transmits power of the mold drive unit 171 to the movable mold 161.Under the control of the control device 500, the mold clamping device170 drives the mold drive unit 171 to move the movable mold 161 to openand close the mold unit 160.

In the present embodiment, a protruding mechanism 180 is provided in themold unit 160. The protruding mechanism 180 includes an ejector pin 181,a first ejector plate 182, a second ejector plate 183, a return pin 184,and a spring member 185. The ejector pin 181 is inserted into a throughhole provided in the movable mold 161. The ejector pin 181 protrudesfrom the movable mold 161 toward the fixed mold 162 by a movement of themovable mold 161 when the mold is opened, and pushes out the moldedobject from the movable mold 161. The ejector pin 181 is fixed to thefirst ejector plate 182 and the second ejector plate 183. A thrustbearing 186 is fixed to a surface of the second ejector plate 183 on the+Y direction side. The return pin 184 is disposed parallel to theejector pin 181. The return pin 184 is inserted into the through holeprovided in the movable mold 161. The return pin 184 is fixed to thefirst ejector plate 182 and the second ejector plate 183. The springmember 185 that biases the first ejector plate 182 from a −Y directiontoward the +Y direction is disposed on an outer periphery of the returnpin 184 between the movable mold 161 and the first ejector plate 182.

FIG. 8 is a perspective view showing a schematic configuration of theinspection device 300 according to the present embodiment. Theinspection device 300 inspects the molded object molded by the injectionmolding machine 100. In the present embodiment, the inspection device300 includes an inspection unit 310, a first placement unit 320, asecond placement unit 330, and a moving unit 340.

The inspection unit 310 includes a camera 315. The inspection unit 310inspects whether the molded object has a predetermined externaldimension by using an image captured by the camera 315. Information onan inspection result of the molded object by the inspection unit 310 istransmitted to the control device 500. The first placement unit 320 andthe second placement unit 330 are disposed below the camera 315. Themolded object molded by the injection molding machine 100 is placed onthe first placement unit 320 and the second placement unit 330.

The moving unit 340 changes a relative position between the firstplacement unit 320 and the inspection unit 310 and a relative positionbetween the second placement unit 330 and the inspection unit 310. Inthe present embodiment, the moving unit 340 includes a first linearactuator 341, a second linear actuator 342, and a third linear actuator343. The first linear actuator 341 and the second linear actuator 342are disposed along the Y direction. The third linear actuator 343 isdisposed along the X direction above the first linear actuator 341 andthe second linear actuator 342. The first linear actuator 341 moves thefirst placement unit 320 along the Y direction. The second linearactuator 342 moves the second placement unit 330 along the Y direction.The third linear actuator 343 moves the inspection unit 310 along the Xdirection. The linear actuators 341 to 343 are driven under the controlof the control device 500.

The inspection device 300 is provided with a first delivery position P31for delivering the molded object between the robot 200 and the firstplacement unit 320, a first inspection position P32 for inspecting themolded object placed on the first placement unit 320, a second deliveryposition P33 for delivering the molded object between the robot 200 andthe second placement unit 330, and a second inspection position P34 forinspecting the molded object placed on the second placement unit 330. Inthe present embodiment, the first delivery position P31 is disposed atan end portion of the first linear actuator 341 on the +Y directionside, and the first inspection position P32 is disposed at an endportion of the first linear actuator 341 on a −Y direction side. Thesecond delivery position P33 is disposed at an end portion of the secondlinear actuator 342 on the +Y direction side, and the second inspectionposition P34 is disposed at an end portion of the second linear actuator342 on the −Y direction side. The taking-out position P11, the firstdelivery position P31, and the second delivery position P33 are disposedin this order from a +X direction to the −X direction.

FIG. 9 is a first top view showing a schematic configuration of the traymoving unit 400. FIG. 10 is a second top view showing the schematicconfiguration of the tray moving unit 400. The tray moving unit 400includes the tray discharging mechanism 405, a rail unit 406, a firstfixed plate 410, a first ball 411, a second fixed plate 415, a secondball 416, a first movable plate 420, a second movable plate 430, a firstdrive unit 441, a second drive unit 442, a third drive unit 443, afourth drive unit 444, and a fixing portion 445. FIG. 9 shows the traymoving unit 400 in a state in which the tray discharging mechanism 405is accommodated in the housing 50. FIG. 10 shows the tray moving unit400 in a state in which the tray discharging mechanism 405 protrudesfrom the housing 50. In FIG. 10 , the first movable plate 420 and thesecond movable plate 430 are indicated by two-dot chain lines.

The tray discharging mechanism 405 includes a plate member and a motor,a gear, or the like for sliding the plate member. The rail unit 406 isdisposed below the tray discharging mechanism 405 along the X direction.The rail unit 406 is fixed to the second base 52 of the housing 50. Thetray discharging mechanism 405 slides on the rail unit 406 from the −Xdirection toward the +X direction to be accommodated in the housing 50as shown in FIG. 9 , and slides on the rail unit 406 from the +Xdirection toward the −X direction to protrude from the housing 50 asshown in FIG. 10 .

The first fixed plate 410 is fixed to an upper surface of the platemember of the tray discharging mechanism 405. The first fixed plate 410is provided with a plurality of first balls 411 rotatable with respectto the first fixed plate 410. In the present embodiment, the first balls411 are rotatably provided in a plurality of holes provided in the firstfixed plate 410. The second fixed plate 415 is fixed to the second base52 of the housing 50. The second fixed plate 415 is disposed on the +Ydirection side with respect to the tray discharging mechanism 405. Thesecond fixed plate 415 is provided with a plurality of second balls 416rotatable with respect to the second fixed plate 415. In the presentembodiment, the second balls 416 are rotatably provided in a pluralityof holes provided in the second fixed plate 415.

The first movable plate 420 and the second movable plate 430 aredisposed above the first fixed plate 410 and the second fixed plate 415.Each of the movable plates 420 and 430 is a rectangular plate member.The tray TR is placed on upper surfaces of the movable plates 420 and430. A first frame portion 422 for preventing a positional deviation ofthe tray TR is provided at an outer peripheral edge of the first movableplate 420. A first hole portion 426 is provided at an end portion of thefirst movable plate 420 on a +X direction side. At each of end portionsof the first movable plate 420 on the −Y direction side and the +Ydirection side, a first cutout portion 427 is provided so that the trayTR can be easily placed on the first movable plate 420 or the tray TRcan be easily taken out from the first movable plate 420. A second frameportion 432 for preventing a positional deviation of the tray TR isprovided at an outer peripheral edge of the second movable plate 430. Asecond hole portion 436 is provided at an end portion of the secondmovable plate 430 on the +X direction side. At each of end portions ofthe second movable plate 430 on the −Y direction side and the +Ydirection side, a second cutout portion 437 is provided so that the trayTR can be easily placed on the second movable plate 430 or the tray TRcan be easily taken out from the second movable plate 430. The movableplates 420 and 430 respectively slide on the first ball 411 and thesecond ball 416 independently of each other to convey the tray TR.

The first drive unit 441 is fixed to an end portion of the first fixedplate 410 on the −X direction side. The first drive unit 441 moves themovable plates 420 and 430 from the −X direction toward the +Xdirection. The second drive unit 442 is fixed to an end portion of thefirst fixed plate 410 on the +X direction side. The second drive unit442 moves the movable plates 420 and 430 from the +X direction towardthe −X direction. The third drive unit 443 is disposed on the −Ydirection side with respect to the first fixed plate 410. The thirddrive unit 443 is fixed to the second base 52 of the housing 50. Thethird drive unit 443 moves the movable plates 420 and 430 from the −Ydirection toward the +Y direction. The fourth drive unit 444 is disposedon the +Y direction side with respect to the second fixed plate 415. Thefourth drive unit 444 is fixed to the second base 52. The fourth driveunit 444 moves the movable plates 420 and 430 from the +Y directiontoward the −Y direction. In the present embodiment, each of the driveunits 441 to 444 is implemented by an air cylinder that pushes out themovable plates 420 and 430. Each of the drive units 441 to 444 may notbe implemented by an air cylinder, but by a motor, a solenoid, or thelike.

The fixing portion 445 fixes the movable plates 420 and 430 on thesecond fixed plate 415. In the present embodiment, the fixing portion445 includes pins protruding downward, and the movable plates 420 and430 are fixed by fitting the pins into the hole portions 426 and 436 ofthe movable plates 420 and 430. The fixing portion 445 may include a padinstead of the pins, and the movable plates 420 and 430 may be fixed bypressing the movable plates 420 and 430 with the pad.

A work area for moving the tray TR is provided on the tray moving unit400. In the present embodiment, the work area is provided with aplacement position P41, a first standby position P42, a second standbyposition P43, and a discharge position P44. The placement position P41is provided on the second fixed plate 415. The first standby positionP42 and the second standby position P43 are provided on the traydischarging mechanism 405 accommodated in the housing 50 and on thefirst fixed plate 410. The discharge position P44 is provided on aportion of the tray discharging mechanism 405 protruding from thehousing 50 that protrudes from the housing 50 and on the first fixedplate 410. The discharge position P44, the first standby position P42,and the second standby position P43 are provided in this order from the−X direction to the +X direction. The first standby position P42 isprovided on the −Y direction side with respect to the placement positionP41. The placement position P41 is a position where the molded object isplaced on the tray TR by the robot 200. The first standby position P42and the second standby position P43 are positions for standing by forthe tray TR. The discharge position P44 is a position where the tray TRis placed on the movable plates 420 and 430, and a position where thetray TR is taken out from the movable plates 420 and 430. A center ofthe placement position P41 is positioned in the X direction between thefirst delivery position P31 and the second delivery position P33 shownin FIG. 4 . Details of the operation of the tray moving unit 400 will bedescribed later.

FIG. 11 is a diagram showing a process of manufacturing the moldedobject by the injection molding system 10 according to the presentembodiment. First, in a molding step of step S110, a molded object ismolded by the injection molding machine 100. Next, in a first conveyancestep of step S120, the robot 200 takes out the molded object from themold unit 160 of the injection molding machine 100, and conveys themolded object from the mold unit 160 to the first placement unit 320 orthe second placement unit 330 of the inspection device 300. In the firstconveyance step, at the taking-out position P11, the molded object istaken out from the mold unit 160 by the robot 200. The molded objecttaken out from the mold unit 160 is conveyed by the robot 200 to beplaced on the first placement unit 320 disposed at the first deliveryposition P31 or the second placement unit 330 disposed at the seconddelivery position P33.

Thereafter, in an inspection step of step S130, the molded object isinspected by the inspection device 300. When the molded object is placedon the first placement unit 320 in the first conveyance step, in theinspection step, the first placement unit 320 is moved from the firstdelivery position P31 to the first inspection position P32, the moldedobject is inspected by the inspection unit 310, and then the firstplacement unit 320 is moved from the first inspection position P32 tothe first delivery position P31. When the molded object is placed on thesecond placement unit 330 in the first conveyance step, in theinspection step, the second placement unit 330 is moved from the seconddelivery position P33 to the second inspection position P34, the moldedobject is inspected by the inspection unit 310, and then the secondplacement unit 330 is moved from the second inspection position P34 tothe second delivery position P33.

In a second conveyance step of step S140, the molded object afterinspection is conveyed from the inspection device 300 to the tray TR bythe robot 200. When the molded object placed on the first placement unit320 is inspected in the inspection step, in the second conveyance step,the robot 200 takes out the molded object after the inspection from thefirst placement unit 320 that has moved to the first delivery positionP31. The molded object taken out from the first placement unit 320 isconveyed by the robot 200 to be placed on the tray TR disposed at theplacement position P41. When the molded object placed on the secondplacement unit 330 is inspected in the inspection step, in the secondconveyance step, the robot 200 takes out the molded object after theinspection from the second placement unit 330 that has moved to thesecond delivery position P33. The molded object taken out from thesecond placement unit 330 is conveyed by the robot 200 to be placed onthe tray TR disposed at the placement position P41. In a thirdconveyance step of step S150, the tray TR on which the molded objectafter the inspection is placed is conveyed by the tray moving unit 400from the placement position P41 to the discharge position P44 to bedischarged to the outside of the housing 50.

FIG. 12 is a time chart showing the process of manufacturing the moldedobject by the injection molding system 10 according to the presentembodiment. In the present embodiment, the injection molding machine 100repeatedly molds the molded object by repeating the molding step. In thepresent embodiment, the control device 500 controls the injectionmolding machine 100, the robot 200, and the inspection device 300 tooverlap a period during which the inspection step is performed for apreviously molded object and a period during which the molding step isperformed for a subsequently molded object, and overlap a period duringwhich the second conveyance step is performed for the previously moldedobject and a period during which the inspection step is performed forthe subsequently molded object. The overlapping of the periods meansthat the two periods coincide with each other, one of the two periods isincluded in the other period, and a portion of one of the two periodsoverlaps with a portion of the other period. In the followingdescription, the molded object molded in the first molding step isreferred to as a first molded object, the molded object molded in thesecond molding step is referred to as a second molded object, and themolded object molded in the third molding step is referred to as a thirdmolded object.

During a period from a timing t10 to a timing t11, the molding step isperformed for the first molded object. During a period from the timingt11 to a timing t12, the first conveyance step is performed for thefirst molded object. During a period from the timing t12 to a timingt13, the inspection step is performed for the first molded object.During a period from a timing t15 to a timing t16, the second conveyancestep is performed for the first molded object. During a period from thetiming t16 to a timing t19, the third conveyance step is performed forthe first molded object.

During the period from the timing t12 to the timing t13, the moldingstep is performed for the second molded object. Therefore, the periodduring which the inspection step is performed for the first moldedobject coincides with the period during which the molding step isperformed for the second molded object. During a period from the timingt13 to a timing t14, the first conveyance step is performed for thesecond molded object. During a period from the timing t14 to a timingt17, the inspection step is performed for the second molded object.Therefore, the period during which the inspection step is performed forthe second molded object coincides with the period during which thesecond conveyance step is performed for the first molded object. Duringa period from the timing t19 to a timing t20, the second conveyance stepis performed for the second molded object. During a period from thetiming t20 to a timing t22, the third conveyance step is performed forthe second molded object.

During the period from the timing t14 to the timing t17, the moldingstep is performed for the third molded object. Therefore, the periodduring which the inspection step is performed for the second moldedobject coincides with the period during which the molding step isperformed for the third molded object, and includes the period duringwhich the second conveyance step is performed for the first moldedobject. During a period from the timing t17 to a timing t18, the firstconveyance step is performed for the third molded object. During aperiod from the timing t18 to the timing t21, the inspection step isperformed for the third molded object. Therefore, the period duringwhich the inspection step is performed for the third molded objectincludes the period during which the second conveyance step is performedfor the second molded object. During a period from the timing t22 to atiming t23, the second conveyance step is performed for the third moldedobject. During a period from the timing t23 to the timing t24, the thirdconveyance step is performed for the third molded object.

FIG. 13 is a flowchart showing contents of a molding processing formolding the molded object. FIG. 13 shows the contents of a processingfor implementing the molding step for molding the first molded objectand the first conveyance step for conveying the first molded object.This processing is executed by the control device 500 when thepredetermined start operation is performed, by the user, on theoperation panel 55 provided in the housing 50. First, in step S210, thecontrol device 500 controls the injection molding machine 100 to executea molding operation in which the mold unit 160 is closed to inject themolten material to the mold unit 160, and then controls the robot 200 toexecute a taking-out preparation operation for preparing the taking-outof the molded object from the mold unit 160 by the robot 200. In thetaking-out preparation operation, the control device 500 causes thesuction unit 250 of the robot 200 to stand by in a vicinity of the moldunit 160.

Next, in step S220, the control device 500 determines whether an erroroccurs in the injection molding machine 100 in the molding operation ofthe injection molding machine 100. In the present embodiment, thecontrol device 500 determines that an error occurs in the injectionmolding machine 100 in at least one of a case where an injection failurein which the molten material is not normally injected from the nozzle155 is detected and a case where a mold clamping failure in which themold unit 160 is not normally clamped is detected. When at least one ofa magnitude of a load of the drive motor 122 of the plasticization unit120 and a magnitude of a load of the motor of the plunger drive unit 153is equal to or larger than a predetermined magnitude, an injectionfailure is detected by the control device 500. When a magnitude of aload of the motor of the mold drive unit 171 is equal to or larger thana predetermined magnitude, a mold clamping failure is detected by thecontrol device 500. The magnitude of the load of the drive motor 122 ofthe plasticization unit 120 can be measured using a magnitude of acurrent supplied to the drive motor 122 of the plasticization unit 120.The magnitude of the load of the plunger drive unit 153 can be measuredusing a magnitude of a current supplied to the motor of the plungerdrive unit 153. The magnitude of the load of the motor of the mold driveunit 171 can be measured using a magnitude of a current supplied to themotor of the mold drive unit 171.

When it is determined in step S220 that an error occurs in the injectionmolding machine 100, in step S270, the control device 500 controls theinjection molding machine 100 and the robot 200 to cause the injectionmolding machine 100 and the robot 200 to execute return operations. Inthe present embodiment, after the return operation of the injectionmolding machine 100 is ended, the control device 500 causes the robot200 to start the return operation. In the return operation of theinjection molding machine 100, the control device 500 moves the movablemold 161 to an origin position thereof. The origin position of themovable mold 161 is a position of the movable mold 161 in which the moldunit 160 is opened. In the return operation of the robot 200, thecontrol device 500 moves the suction unit 250 and the arm unit 210 ofthe robot 200 to respective preset origin positions.

When it is determined in step S220 that an error does not occur in theinjection molding machine 100, in step S230, the control device 500controls the injection molding machine 100 to push out the molded objectfrom the movable mold 161 by the ejector pin 181, and in step S240, thecontrol device 500 causes the robot 200 to execute a taking-outoperation of sucking the molded object by the suction unit 250 and thentaking out the molded object pushed out by the ejector pin 181.

In step S250, the control device 500 determines whether an error occursin the robot 200 in the taking-out operation of the robot 200. In thepresent embodiment, the control device 500 determines that an erroroccurs in the robot 200 when a suction failure in which the moldedobject is not normally sucked by the suction unit 250 of the robot 200is detected. A pressure gauge is provided inside the suction unit 250,and the control device 500 can detect a suction failure by using apressure value of the air measured by the pressure gauge.

When it is determined in step S250 that an error occurs in the robot200, in step S270, the control device 500 controls the injection moldingmachine 100 and the robot 200 to cause the injection molding machine 100and the robot 200 to execute the return operations as described above.On the other hand, when it is determined in step S250 that an error doesnot occur in the robot 200, in step S260, the control device 500controls the robot 200 to convey the molded object sucked by the suctionunit 250 to the inspection device 300 to end the processing.

FIGS. 14 and 16 are diagrams showing states in which a molded object MDis protruded from the movable mold 161 by the ejector pin 181. In FIG.14 , a space between the movable mold 161 and the fixed mold 162 isclosed. As shown in FIG. 15 , the control device 500 moves the movablemold 161 in a direction away from the fixed mold 162. At this time, theejector pin 181 moves together with the movable mold 161 until thethrust bearing 186 shown in FIG. 5 comes into contact with a tip endportion of the ball screw unit 172. A movement of the ejector pin 181 inthe direction away from the fixed mold 162 is restricted by bringing thethrust bearing 186 into contact with the tip end portion of the ballscrew unit 172. When the thrust bearing 186 comes into contact with thetip end portion of the ball screw unit 172, the control device 500temporarily stops the movement of the movable mold 161, and moves thesuction unit 250 between the movable mold 161 and the fixed mold 162.The control device 500 causes the suction unit 250 to suck the moldedobject MD in a state where a distance between the molded object MD andthe fixed mold 162 is kept at a predetermined distance d. After themolded object MD is sucked by the suction unit 250, the control device500 restarts the movement of the movable mold 161 as shown in FIG. 16 .Since the movement of the ejector pin 181 in the direction away from thefixed mold 162 is restricted, the ejector pin 181 is protruded from themovable mold 161 toward the fixed mold 162 by the movement of themovable mold 161 to push out the molded object MD from the movable mold161. When the molded object MD is pushed out from the movable mold 161,the distance between the molded object MD and the fixed mold 162 is keptat the predetermined distance d. Thereafter, when the movable mold 161moves in a direction approaching the fixed mold 162, the first ejectorplate 182 is biased by the spring member 185 to accommodate the ejectorpin 181 in the through hole of the movable mold 161.

FIG. 17 is a reference diagram showing a state in which the moldedobject MD is protruded by an ejector pin 181 b according to anotherform. In another form shown in FIG. 17 , the ejector pin 181 b moveswith respect to the movable mold 161 and the fixed mold 162, and theejector pin 181 b protrudes from the movable mold 161 toward the fixedmold 162, thereby pushing out the molded object MD from the movable mold161. In this form, the distance between the molded object MD and thefixed mold 162 changes before and after the molded object MD is pushedout from the movable mold 161. Therefore, an operation of the robot 200when the molded object MD is sucked by the suction unit 250 iscomplicated. In addition, since a motor or the like for moving theejector pin 181 b is required, the configuration of the injectionmolding machine 100 is complicated.

The inspection step will be described with reference to FIG. 8 . Afterthe molded object is placed on the first placement unit 320, the controldevice 500 controls the moving unit 340 to move the first placement unit320 from the first delivery position P31 to the first inspectionposition P32, and then move the inspection unit 310 from the secondinspection position P34 to the first inspection position P32. After themolded object placed on the first placement unit 320 is inspected by theinspection unit 310 at the first inspection position P32, the controldevice 500 controls the moving unit 340 to move the first placement unit320 from the first inspection position P32 to the first deliveryposition P31. After the molded object is placed on the second placementunit 330, the control device 500 controls the moving unit 340 to movethe second placement unit 330 from the second delivery position P33 tothe second inspection position P34, and then move the inspection unit310 from the first inspection position P32 to the second inspectionposition P34. After the molded object placed on the second placementunit 330 is inspected by the inspection unit 310 at the secondinspection position, the control device 500 controls the moving unit 340to move the second placement unit 330 from the second inspectionposition P34 to the second delivery position P33. When the inspectedmolded object has the predetermined external dimension, the controldevice 500 controls the robot 200 to convey the molded object after theinspection from the inspection device 300 to the tray TR. On the otherhand, when the molded object does not have the predetermined externaldimension, the control device 500 controls the robot 200 to convey themolded object after the inspection from the inspection device 300 to adisposal box (not shown).

FIGS. 18 to 22 are diagrams showing operations of the tray moving unit400. Referring to FIG. 18 , in an initial state of step S405, the firstmovable plate 420 is disposed at the first standby position P42, and thesecond movable plate 430 is disposed at the placement position P41. Instep S410, the control device 500 drives the tray discharging mechanism405 to cause the tray discharging mechanism 405 to protrude to theoutside of the housing 50. When the tray discharging mechanism 405protrudes to the outside of the housing 50, the first movable plate 420moves from the first standby position P42 to the discharge position P44.For example, when the operation panel 55 provided in the housing 50 isoperated by the user, the control device 500 drives the tray dischargingmechanism 405. In step S415, the control device 500 drives the fourthdrive unit 444 to move the second movable plate 430 from the placementposition P41 to the first standby position P42.

Referring to FIG. 19 , in step S420, an empty first tray TR1 is placedon the first movable plate 420 disposed at the discharge position P44.In the present embodiment, the first tray TR1 is placed on the firstmovable plate 420 by the user. In step S425, the control device 500drives the tray discharging mechanism 405 to accommodate, in the housing50, the tray discharging mechanism 405 protruding to the outside of thehousing 50. When the tray discharging mechanism 405 is accommodated inthe housing 50, the first movable plate 420 on which the first tray TR1is placed moves from the discharge position P44 to the first standbyposition P42, and the second movable plate 430 moves from the firststandby position P42 to the second standby position P43. In step S430,the control device 500 drives the third drive unit 443 to move the firstmovable plate 420 on which the first tray TR1 is placed from the firststandby position P42 to the placement position P41, and drives thefixing portion 445 to fix the first movable plate 420 on which the firsttray TR1 is placed to the placement position P41. After the firstmovable plate 420 on which the first tray TR1 is placed is fixed to theplacement position P41, placement of the molded object MD on the firsttray TR1 is started by the robot 200.

Referring to FIG. 20 , in step S435, the control device 500 drives thesecond drive unit 442 to move the second movable plate 430 from thesecond standby position P43 to the first standby position P42. In stepS440, the control device 500 drives the tray discharging mechanism 405to cause the tray discharging mechanism 405 to protrude to the outsideof the housing 50. When the tray discharging mechanism 405 protrudes tothe outside of the housing 50, the second movable plate 430 moves fromthe first standby position P42 to the discharge position P44. In stepS445, the control device 500 drives the fixing portion 445 to releasethe fixing of the first movable plate 420 on which the first tray TR1 isplaced, and then drives the fourth drive unit 444 to move the firstmovable plate 420 on which the first tray TR1 is placed from theplacement position P41 to the first standby position P42.

Referring to FIG. 21 , in step S450, a second tray TR2 is placed on thesecond movable plate 430 disposed at the discharge position P44. In thepresent embodiment, the second tray TR2 is placed on the second movableplate 430 by the user. In step S455, the control device 500 drives thetray discharging mechanism 405 to accommodate the tray dischargingmechanism 405 in the housing 50. When the tray discharging mechanism 405is accommodated in the housing 50, the first movable plate 420 on whichthe first tray TR1 is placed moves from the first standby position P42to the second standby position P43, and the second movable plate 430 onwhich the second tray TR2 is placed moves from the discharge positionP44 to the first standby position P42. In step S460, the control device500 drives the third drive unit 443 to move the second movable plate 430on which the second tray TR2 is placed from the first standby positionP42 to the placement position P41, and drives the fixing portion 445 tofix the second movable plate 430 to the placement position P41. Afterthe second movable plate 430 on which the second tray TR2 is placed isfixed to the placement position P41, the placement of the molded objectMD on the second tray TR2 is started by the robot 200.

Referring to FIG. 22 , in step S465, the control device 500 drives thesecond drive unit 442 to move the first movable plate 420 on which thefirst tray TR1 is placed from the second standby position P43 to thefirst standby position P42. In step S470, the control device 500 drivesthe tray discharging mechanism 405 to cause the tray dischargingmechanism 405 to protrude to the outside of the housing 50. When thetray discharging mechanism 405 protrudes to the outside of the housing50, the first movable plate 420 on which the first tray TR1 is placedmoves from the first standby position P42 to the discharge position P44.In step S475, the first tray TR1 on which the molded object MD is placedis taken out from the first movable plate 420 disposed at the dischargeposition P44. In the present embodiment, the first tray TR1 is taken outfrom the first movable plate 420 by the user.

Thereafter, the processings from step S415 to step S475 are repeated. Anempty third tray is placed on the first movable plate 420 disposed atthe discharge position P44 to move to the placement position P41, andthe second movable plate 430 on which the second tray TR2 is placedmoves to the discharge position P44. The third tray may not be used. Forexample, after the first tray TR1 is taken out from the first movableplate 420 and the molded object is taken out from the first tray TR1,the first tray TR1 may be placed on the first movable plate 420 again.The molded object MD may be taken out from the first tray TR1 while thefirst tray TR1 is placed on the first movable plate 420.

FIG. 23 is a time chart showing a process of manufacturing the moldedobject according to a comparative example. In the comparative example,the second delivery position P33 and the second inspection position P34are not provided. Therefore, the first conveyance step cannot beperformed for the second molded object until the second conveyance stepfor the first molded object is ended. A waiting time for moving therobot 200 from the placement position P41 to the taking-out position P11occurs between the end of the second conveyance step for the firstmolded object and the start of the first conveyance step for the secondmolded object. Therefore, a timing at which the first conveyance step isstarted for the second molded object in the comparative example is laterthan a timing at which the first conveyance step is started for thesecond molded object in the present embodiment. As a result, a timing atwhich the molding step is started for the third molded object in thecomparative example is later than a timing at which the molding step isstarted for the third molded object in the present embodiment.

According to the injection molding system 10 of the present embodimentdescribed above, the control device 500 controls the injection moldingmachine 100, the robot 200, and the inspection device 300 to overlap theperiod during which the inspection step is performed for inspecting thefirst molded object and the period during which the molding step isperformed for molding the second molded object, and overlap the periodduring which the inspection step is performed for inspecting the secondmolded object and the period during which the second conveyance step isperformed for conveying the first molded object to the tray. Therefore,since the molding step for molding the third molded object can bestarted at an early stage, the cycle time can be shortened. Inparticular, in the present embodiment, the control device 500 controlsthe injection molding machine 100, the robot 200, and the inspectiondevice 300 to overlap the period during which the molding step isperformed for molding the third molded object and the period duringwhich the second conveyance step is performed for conveying the firstmolded object from the inspection device 300 to the tray TR. Therefore,the cycle time can be reliably shortened.

In the present embodiment, the inspection device 300 is configured suchthat while the molded object placed on one of the first placement unit320 and the second placement unit 330 is inspected by the inspectionunit 310, the molded object can be delivered between the other one ofthe first placement unit 320 and the second placement unit 330 and therobot 200. Therefore, the inspection step for inspecting the secondmolded object and the second conveyance step for conveying the firstmolded object to the tray can be overlapped without providing aplurality of inspection units 310. In particular, in the presentembodiment, the inspection device 300 is configured such that while themolded object by the inspection unit 310 is inspected at the firstinspection position P32, it is possible to deliver the molded objectbetween the robot 200 and the second placement unit 330 at the seconddelivery position P33 away from the first inspection position P32, andwhile the molded object by the inspection unit 310 is inspected at thesecond inspection position P34, it is possible to deliver the moldedobject between the robot 200 and the first placement unit 320 at thefirst delivery position P31 away from the second inspection positionP34. Therefore, a possibility of collision between the inspection unit310 and the robot 200 can be reduced.

In the present embodiment, a center of the taking-out position P11, acenter of the first delivery position P31, the center of the placementposition P41, and a center of the second delivery position P33 aredisposed in this order from the +X direction to the −X direction.Therefore, a moving distance of the suction unit 250 in the X directioncan be shortened as compared with the form in which the center of thetaking-out position P11, the center of the first delivery position P31,the center of the second delivery position P33, and the center of theplacement position P41 are disposed in this order from the +X directionto the −X direction.

In the present embodiment, the empty second tray TR2 can be moved fromthe discharge position P44 to the placement position P41 while the firsttray TR1 on which the molded object is placed is moved from theplacement position P41 to the discharge position P44 by the tray movingunit 400. Therefore, since the waiting time until the first tray TR1disposed at the placement position P41 is replaced with the second trayTR2 can be shortened as compared with the form in which the first trayTR1 on which the molded object is placed is moved from the placementposition P41 to the discharge position P44 and then the empty secondtray TR2 is moved from the discharge position P94 to the placementposition P41, the cycle time can be shortened. In particular, in thepresent embodiment, the empty second tray TR2 can be moved toward theplacement position P41 while the first tray TR1 on which the firstmolded object is placed is taken out at the discharge position P44.Therefore, the taking-out of the first tray TR1 at the dischargeposition P44 and the placement of the second molded object on the secondtray TR2 at the placement position P41 can be performed in parallel.

In present embodiment, according to the injection molding system of thisform, the tray moving unit 400 is configured such that the dischargeposition P44, the first standby position P42, and the second standbyposition P43 are disposed in this order from the −X direction toward the+X direction, and the placement position P41 is disposed on the +Ydirection side of the first standby position P42. Therefore, the traycan be moved efficiently in a space-saving work area.

In the present embodiment, the first tray TR1 on which the first moldedobject is placed and the second tray TR2 on which the second moldedobject is placed can be moved to the discharge position P44 protrudingfrom the housing 50 by the tray discharging mechanism 405. Therefore,the first tray TR1 on which the first molded object is placed and thesecond tray TR2 on which the second molded object is placed can beeasily taken out to the outside of the housing 50.

In the present embodiment, when an error occurs due to at least one ofthe operation of the injection molding machine 100 and the operation ofthe robot 200, the control device 500 causes both the injection moldingmachine 100 and the robot 200 to perform return operations. Therefore,regardless of whether the error is caused by the operation of theinjection molding machine 100 or caused by the operation of the robot200, the injection molding machine 100 and the robot 200 can be reliablyreturned from the error.

In the present embodiment, when an error occurs due to at least one ofthe operation of the injection molding machine 100 and the operation ofthe robot 200, the control device 500 starts the return operation of therobot 200 after the return operation of the injection molding machine100 is ended. Therefore, the return operation of the injection moldingmachine 100 and the return operation of the robot 200 can be preventedfrom being performed in parallel, so that a possibility of collisionbetween the injection molding machine 100 and the robot 200 can bereduced.

In the present embodiment, the control device 500 determines that anerror occurs in the injection molding machine 100 in at least one of acase where an injection failure in which the molten material is notnormally injected from the nozzle 155 is detected and a case where amold clamping failure in which the mold unit 160 is not normally clampedis detected. Therefore, it is possible to eliminate the error of theinjection molding machine 100 caused by the injection failure or themold clamping failure.

In the present embodiment, the control device 500 determines that anerror occurs in the robot 200 when a suction failure in which the moldedobject is not normally sucked in the suction unit 250 is detected.Therefore, it is possible to eliminate the error of the robot 200 causedby the suction failure.

In the present embodiment, the injection molding machine 100 and thetray moving unit 400 vertically overlap each other in the verticaldirection. Therefore, the injection molding system 10 can be downsizedin the horizontal direction.

In the present embodiment, the inspection device 300 and the tray movingunit 400 vertically overlap each other in the vertical direction.Therefore, the injection molding system 10 can be downsized in thehorizontal direction.

In the present embodiment, the molded object can be pushed out from themovable mold 161 by the ejector pin 181 without changing an intervalbetween the fixed mold 162 and the molded object MD. Therefore, sincethe position of the molded object MD is fixed when the suction unit 250of the robot 200 sucks the molded object MD, the molded object MD can beeasily sucked by the suction unit 250 of the robot 200.

In the present embodiment, the injection molding machine 100 melts thematerial using the flat screw 130 having a small height in the directionalong the central axis RX. Therefore, since the injection moldingmachine 100 can be downsized, the injection molding system 10 can bedownsized.

B. Other Embodiments

(B1) In the injection molding system 10 according to the embodimentdescribed above, the inspection device 300 is provided with the firstinspection position P32 and the second inspection position P34, and themoving unit 340 reciprocates the inspection unit 310 between the firstinspection position P32 and the second inspection position P34. Incontrast, the first inspection position P32 and the second inspectionposition P34 may be provided at the same position in the inspectiondevice 300. For example, one inspection position may be provided in theinspection device 300, and the inspection unit 310 may be fixed abovethe inspection position. In this case, the moving unit 340 is configuredto reciprocate the first placement unit 320 between the first deliveryposition P31 and the inspection position, and to reciprocate the secondplacement unit 330 between the second delivery position P33 and theinspection position. In the inspection device 300, the first inspectionposition P32 and the first delivery position P31 may be provided at thesame position, and the second inspection position P34 and the seconddelivery position P33 may be provided at the same position. In thiscase, the moving unit 340 is configured to move the inspection unit 310between the first placement unit 320 and the second placement unit 330without moving the first placement unit 320 and the second placementunit 330.

(B2) In the injection molding system 10 according to the above-describedembodiment, the control device 500 starts the molding step for moldingthe second molded object by the injection molding machine 100 while thefirst molded object is placed on the first placement unit 320 or thesecond placement unit 330 of the inspection device 300. In contrast, thecontrol device 500 may start the molding step for molding the secondmolded object by the injection molding machine 100 after the firstmolded object is taken out from the mold unit 160 by the robot 200 andbefore the first molded object is placed on the first placement unit 320or the second placement unit 330 of the inspection device 300. In thiscase, the cycle time can be further shortened.

(B3) In the injection molding system 10 according to the embodimentdescribed above, the center of the taking-out position P11, the centerof the first delivery position P31, the center of the placement positionP41, and the center of the second delivery position P33 are disposed inthis order from the +X direction to the −X direction. In contrast, thecenter of the taking-out position P11, the center of the first deliveryposition P31, the center of the placement position P41, and the centerof the second delivery position P33 may be disposed in an orderdifferent from that described above. For example, the center of thetaking-out position P11, the center of the first delivery position P31,the center of the second delivery position P33, and the center of theplacement position P41 may be disposed in this order from the +Xdirection to the −X direction.

(B4) In the injection molding system 10 according to the embodimentdescribed above, the tray moving unit 400 includes the tray dischargingmechanism 405 protruding to the outside of the housing 50, and thedischarge position P44 is provided on the tray discharging mechanism 405protruding from the housing 50. In contrast, the tray moving unit 400may not include the tray discharging mechanism 405, and the dischargeposition P44 may be provided in the housing 50.

(B5) In the injection molding system 10 according to the embodimentdescribed above, the tray moving unit 400 may be configured such thatthe discharge position P44, the first standby position P42, theplacement position P41, and the second standby position P43 are disposedclockwise, and the first tray TR1 and the second tray TR2 are clockwisemoved in the order of the discharge position P44, the first standbyposition P42, the placement position P41, and the second standbyposition P43. The tray moving unit 400 may be configured such that thedischarge position P44, the first standby position P42, the placementposition P41, and the second standby position P43 are disposedcounterclockwise, and the first tray TR1 and the second tray TR2 arecounterclockwise moved in the order of the discharge position P44, thefirst standby position P42, the placement position P41, and the secondstandby position P43.

(B6) In the injection molding system 10 according to the embodimentdescribed above, when the control device 500 determines in step S270 ofFIG. 13 that an error occurs in at least one of the injection moldingmachine 100 and the robot 200, the control device 500 starts the returnoperation of the robot 200 after the return operation of the injectionmolding machine 100 is ended. In contrast, when the control device 500determines in step S270 that an error occurs in at least one of theinjection molding machine 100 and the robot 200, the return operationsof the injection molding machine 100 and the robot 200 may be executedto overlap a period during which the return operation of the injectionmolding machine 100 is performed and a period during which the returnoperation of the robot 200 is performed.

(B7) In the injection molding system 10 according to the embodimentdescribed above, when it is determined in step S270 of FIG. 13 that anerror occurs in at least one of the injection molding machine 100 andthe robot 200, the control device 500 may cause the inspection device300 to execute a return operation after the inspection of the moldedobject by the inspection device 300 is ended. In this case, it ispossible to prevent the inspection of the molded object by theinspection device 300 from being interrupted, and the inspection of themolded object from being omitted.

(B8) In the injection molding system 10 according to the embodimentdescribed above, when it is determined in step S270 of FIG. 13 that anerror occurs in at least one of the injection molding machine 100 andthe robot 200, the control device 500 may control the tray moving unit400 to move the tray on which the molded object is placed to thedischarge position P44. Therefore, since the tray on which the moldedobject is placed can be conveyed toward the discharge position P44 whilethe return operations of the injection molding machine 100 and the robot200 are executed, it is possible to prevent the discharge of the moldedobject placed on the tray from being delayed before the occurrence ofthe error.

(B9) In the injection molding system 10 according to the embodimentdescribed above, the tray moving unit 400 and at least a part of theinjection molding machine 100 vertically overlap each other in thevertical direction. In contrast, the tray moving unit 400 and at least apart of a fixed portion between the robot 200 and the housing 50 mayvertically overlap each other without vertically overlapping theinjection molding machine 100 and the tray moving unit 400 in thevertical direction. The tray moving unit 400 and at least a part of theinjection molding machine 100 may vertically overlap each other, and thetray moving unit 400 and at least a part of the fixed portion betweenthe robot 200 and the housing 50 may vertically overlap each other inthe vertical direction.

(B10) In the injection molding system 10 according to the embodimentdescribed above, the tray moving unit 400 and at least a part of theinspection device 300 vertically overlap each other in the verticaldirection. In contrast, the inspection device 300 and the tray movingunit 400 may not vertically overlap each other in the verticaldirection.

(B11) In the injection molding system 10 according to the embodimentdescribed above, the injection molding machine 100 is configured to movethe movable mold 161 with respect to the fixed mold 162 and the ejectorpin 181 without moving the ejector pin 181 with respect to the fixedmold 162 when the molded object MD is pushed out from the movable mold161. In contrast, the injection molding machine 100 may be configured tomove the ejector pin 181 with respect to the movable mold 161 and thefixed mold 162 when the molded object MD is pushed out from the movablemold 161.

(B12) In the injection molding system 10 according to the embodimentdescribed above, the injection molding machine 100 includes the flatcolumnar flat screw 130 and the barrel 140 having a flat screw 142facing surface. In contrast, the injection molding machine 100 mayinclude a screw which has a long shaft-shaped outer shape and in which aspiral groove is formed on a side surface of a shaft, and a barrelhaving a cylindrical screw facing surface.

C. Other Aspects

The present disclosure is not limited to the above-describedembodiments, and can be implemented in various aspects without departingfrom the spirit of the present disclosure. For example, the presentdisclosure can be implemented by the following aspects. In order tosolve some or all of the problems described in the present disclosure,or to achieve some or all of the effects of the present disclosure,technical characteristics in the above embodiments corresponding to thetechnical characteristics in each of the embodiments described below canbe appropriately replaced or combined. If the technical characteristicsare not described as essential in the present description, they can bedeleted as appropriate.

(1) According to one aspect of the present disclosure, an injectionmolding system is provided. The injection molding system includes: aninjection molding machine configured to inject a molten material into amold to mold a molded object; an inspection device including a firstplacement unit and a second placement unit on which the molded object isplaced, an inspection unit configured to inspect the molded object, anda moving unit configured to change a relative position between the firstplacement unit and the inspection unit and a relative position betweenthe second placement unit and the inspection unit; a third placementunit on which the molded object after inspection by the inspectiondevice is placed; a robot configured to execute an operation ofconveying the molded object from the mold to the first placement unit orthe second placement unit, and an operation of conveying the moldedobject from the first placement unit or the second placement unit to thethird placement unit; and a control device configured to control theinjection molding machine, the robot, and the inspection device. Thecontrol device controls the injection molding machine, the robot, andthe inspection device so as to mold, by the injection molding machine, afirst molded object as the molded object during a first molding period,inspect, by the inspection unit, the first molded object placed on thefirst placement unit during a first inspection period, convey, by therobot, the first molded object after inspection from the first placementunit to the third placement unit during a first conveyance period, mold,by the injection molding machine, a second molded object that is themolded object during a second molding period after the first moldingperiod, inspect, by the inspection unit, the second molded object placedon the second placement unit during a second inspection period, convey,by the robot, the second molded object after inspection from the secondplacement unit to the third placement unit during a second conveyanceperiod, and overlap the first inspection period and the second moldingperiod and overlap the second inspection period and the first conveyanceperiod.

According to the injection molding system of this aspect, when themolded object placed on one of the first placement unit and the secondplacement unit is inspected, the molded object can be delivered to theother one of the first placement unit and the second placement unit.Therefore, the cycle time can be shortened.

(2) In the injection molding system of the above aspect, the inspectiondevice may include a first delivery position and a second deliveryposition for delivering the molded object between the inspection deviceand the robot, and a first inspection position and a second inspectionposition for inspecting the molded object, and the moving unit may movethe first placement unit between the first delivery position and thefirst inspection position, move the second placement unit between thesecond delivery position and the second inspection position, and movethe inspection unit between the first inspection position and the secondinspection position.

According to the injection molding system of this aspect, since themolded object can be delivered between the robot and the first placementunit or the second placement unit at a position away from the positionwhere the molded object is inspected by the inspection unit, thepossibility of collision between the inspection unit and the robot canbe reduced.

(3) In the injection molding system of the above aspect, the mold, thefirst delivery position, the third placement unit, and the seconddelivery position may be disposed in this order in a direction from thefirst delivery position to the second delivery position.

According to the injection molding system of this aspect, a movingdistance of the robot for conveying the molded object can be shortened.

(4) In the injection molding system of the above aspect, the controldevice may mold, by the injection molding machine, a third molded objectas the molded object during a third molding period overlapping the firstconveyance period.

According to the injection molding system of this aspect, the cycle timecan be further shortened.

(5) In the injection molding system of the above aspect, the controldevice may control the injection molding machine to start molding thesecond molded object by the injection molding machine before the firstmolded object is placed on the first placement unit.

According to the injection molding system of this aspect, the cycle timecan be further shortened.

(6) In the injection molding system of the above aspect, the mold of theinjection molding machine may include a fixed mold, a movable moldmoving with respect to the fixed mold, and an ejector pin protrudingfrom the movable mold toward the fixed mold by a movement of the movablemold with respect to the fixed mold, and the robot may take out, by theejector pin, the molded object pushed out from the movable mold.

According to the injection molding system of this aspect, since themolded object can be released from the movable mold without changing aninterval between the fixed mold and the molded object, the molded objectcan be easily grasped by the robot when the molded object is taken outfrom the movable mold.

(7) In the injection molding system of the above aspect, the injectionmolding machine may include a nozzle configured to inject the moltenmaterial into the mold, a flat screw having a groove forming surfaceprovided with a groove portion, a barrel having a communication holefacing the groove forming surface and communicating with the nozzle, anda heating unit, and by rotation of the flat screw and heating by theheating unit, a material supplied to the groove portion may be melted togenerate the molten material, and then the molten material may flow outfrom the communication hole.

According to the injection molding system of this aspect, since theinjection molding machine can be downsized, the injection molding systemcan be downsized.

The present disclosure may be implemented in various forms other thanthe injection molding system. For example, the present disclosure can beimplemented in the form of a method for manufacturing a molded object.

What is claimed is:
 1. An injection molding system comprising: aninjection molding machine configured to inject a molten material into amold to mold a molded object; an inspection device including a firstplacement unit and a second placement unit, an inspection unitconfigured to inspect the molded object individually placed on one ofthe first placement unit and the second placement unit, and a movingunit configured to switch between inspection at the first placement unitand inspection at the second placement unit by moving the inspectionunit between a first inspection position and a second inspectionposition, and by reciprocating the first placement unit along a firstdirection between a first delivery position and the first inspectionposition to change a relative position between the first placement unitand the inspection unit and reciprocating the second placement unitalong the first direction between a second delivery position and thesecond inspection position to change a relative position between thesecond placement unit and the inspection unit, the first inspectionposition and the second inspection position being aligned along a seconddirection orthogonal to the first direction; a third placement unit onwhich the molded object after inspection by the inspection device isplaced on a tray; a robot configured to execute an operation ofindividually conveying the molded object molded by the injection moldingmachine from a taking-out position to the first placement unit or thesecond placement unit by switching between conveying to the firstplacement unit and conveying to the second placement unit, and anoperation of individually conveying the molded object from the firstplacement unit or the second placement unit to the third placement unitby switching between conveying from the first placement unit andconveying from the second placement unit; and a control deviceconfigured to control the injection molding machine, the robot, and theinspection device, wherein the control device controls the injectionmolding machine, the robot, and the inspection device so as to mold, bythe injection molding machine, a first molded object as the moldedobject during a first molding period, inspect, by the inspection unit,the first molded object individually placed on the first placement unitduring a first inspection period, individually convey, by the robot, thefirst molded object after inspection from the first placement unit tothe third placement unit during a first conveyance period, mold, by theinjection molding machine, a second molded object as the molded objectduring a second molding period after the first molding period, inspect,by the inspection unit, the second molded object individually placed onthe second placement unit during a second inspection period,individually convey, by the robot, the second molded object afterinspection from the second placement unit to the third placement unitduring a second conveyance period, and overlap the first inspectionperiod and the second molding period and overlap the second inspectionperiod and the first conveyance period, and a center of the taking-outposition, a center of the third placement unit, a center of the firstdelivery position and a center of the second delivery position arearranged in this order with respect to the second direction.
 2. Theinjection molding system according to claim 1, wherein the mold, thefirst delivery position, the third placement unit, and the seconddelivery position are disposed in this order in a direction from thefirst delivery position to the second delivery position.
 3. Theinjection molding system according to claim 1, wherein the controldevice molds, by the injection molding machine, a third molded object asthe molded object during a third molding period overlapping the firstconveyance period.
 4. The injection molding system according to claim 1,wherein the control device controls the injection molding machine tostart molding the second molded object by the injection molding machinebefore the first molded object is placed on the first placement unit. 5.The injection molding system according to claim 1, wherein the mold ofthe injection molding machine includes a fixed mold, a movable moldmoving with respect to the fixed mold, and an ejector pin protrudingfrom the movable mold toward the fixed mold by a movement of the movablemold with respect to the fixed mold, and the robot takes out, by theejector pin, the molded object pushed out from the movable mold.
 6. Theinjection molding system according to claim 1, wherein the injectionmolding machine includes a nozzle configured to inject the moltenmaterial into the mold, a flat screw having a groove forming surfaceprovided with a groove portion, a barrel having a communication holefacing the groove forming surface and communicating with the nozzle, anda heating unit, and by rotation of the flat screw and heating by theheating unit, a material supplied to the groove portion is melted togenerate the molten material, and then the molten material flows outfrom the communication hole.